DENVER — Colorado Democrats abandoned their own divisive abortion proposal Wednesday, axing the bill after one lawmaker expressed indecision and it became clear they might not have the votes to pass it in a chamber where every vote matters.

Democrats used a legislative maneuver to shelve a bill that would have banned any state regulation of reproductive decisions such as abortion and contraception. It had been scheduled for a vote Wednesday evening in the Senate, where the party holds a slim one-seat majority.

The move came after Sen. John Kefalas, D-Fort Collins, said he wasn't sure if the measure was the "right tool" to protect a woman's right to manage her reproductive health.

"I totally support a woman's right to make decisions," he said. But referencing an outpouring of opposition in recent days, Kefalas added, "I had concerns about the outpouring that I heard from folks."

At least 500 people protested the measure at the Capitol on Tuesday, led by Denver Catholic Archbishop Samuel Aquila. Aquila argued that the bill was so vague it could have been interpreted to ban any health regulations at women's clinics.

The sponsor of the measure, Democratic Sen. Andy Kerr of Lakewood, said Wednesday that Democrats shelved the measure to avoid gridlock by minority Republicans.

"We weren't ready to let this session be overshadowed" by the abortion measure, Kerr said.

All Republicans planned to vote against the measure, but they insisted they had no plans to use the abortion debate to stall other matters.

"That's ridiculous," Senate Republican Leader Bill Cadman said after the bill died. "What they ran into was a firestorm of public dissent."